Britain's MI5 intelligence service is to hold an inquiry into its handling of information surrounding the Manchester bomber, Salman Abedi, after it emerged that it had been alerted to his extremist views by members of the public at least three times ahead of the attack which killed 22 and wounded dozens outside of an Ariana Grande concert on May 22, 2017, according to British media reports.

MI5 launched a "post incident investigation" into how Abedi was overlooked by the service, the BBC said Monday, as a second, separate inquiry was undertaken for ministers and others who oversee MI5's work. According to the Guardian newspaper, one review will aim to quickly identify any obvious mistakes that may have been made, while the other will take a more in-depth look at possible missteps.

It is highly unusual for authorities in Britain to make public the fact that intelligence services are internally investigating possible lapses.

"I think it's right that MI5 takes a look to find out what the facts are," British Home Secretary Amber Rudd told Sky News. "We shouldn't rush to make any conclusions at this stage," she said.

Ms. Rudd also confirmed that the United Kingdom had begun using temporary exclusion orders, which prevent potential terrorists from returning to Britain after fighting in places like Syria.

They have "just started to be used," she told Sky.

When he was 16 years old, Abedi reportedly travelled during school holidays to fight with his father against the Qaddafi regime in Libya. According to the BBC, two people who knew Abedi during his time at Manchester College confirmed they had each made separate calls to anti-terrorism hotlines to warn authorities about his extremist views.

Meanwhile on Monday, a further arrest was made in the investigation into the Manchester bombing, authorities said, with the detention of a 23-year-old suspect from an address in Shoreham-by-Sea. Searches were conducted in Manchester and Cheshire overnight, and operations were ongoing in Pilsworth, Bury, the Greater Manchester Police confirmed.

In total, 16 people have so far been arrested in connection with the investigation, two of which have been released without charge.